Grinding machine



April 28, 1931.

R. WEBSTER GRINDING MACHINE Filed Jan. 12 1929 I ATTORNEY 5 Sheets-Sheet 1 INVENTOR April 28, 1931- R. WEBSTER GRINDING MACHINE Filed Jan. 12. 1929 5 Sheets-Sheet 2 INVENTOR BYRA MOND WEBSTER ATTORNEY April 28, 1931. WEBSTER 1,802,798

GRINDING MACHINE Filed Jan. 12, 1929 5 Sheets-Sheet 3 INVENTOR BY RAYMOND WEBSTER ATTORNE Apnl 28, 1931. WEBSTER 1,802,798

GRINDING MACHINE I Filed Jan. 12, 1929 5 Sheets- Sheet 4 51 5 ENVENTOR BY RAYMOD WEBSTER April 28, 1931. R. WEBSTER 1,802,798

' GRINDING MACHINE Filed Jan. 12, 1929 5 Sheets-Sheet 5 FIG. 12

III/II 4R" IIIIIIIII/ INVENTOR BY RAYMOND WEBSTER k I I lg). ATTO R N Patented Apr. 28, 1931 e ACT-ZINE The present invention'relates to machines for producing. index plates, gears, and the like and particularly to machines of this type which are fluid pressure operated.

()ne embodiment of the invention is illustrated in the accompanying drawing, in which:

Figure 1 is a vertical sectional view through an index-plate grinding machine constructed according to this invent-ion;

Figure 2 is a plan view of this machine, parts being shown section;

Figure 3 is a rear elevation of the machine;

Figure 4 is a section taken generally on the line l4 of Figure 5 showing details of the index mechanism for the work spindle;

Figure 5 is a section taken'generally on the line'55 otFigure 4i;

Figure 6 is a section taken generally on the line 66 of Figure 4;

Figure 7 is a sectional view of the reversing and throttle valve and associated parts;

Figure 8 is aside elevation ot'this control mechanism, parts being broken away;

Figure 9 is a section on a somewhat enlarged scale take n generally on the line 99 oi Figure 7'; igure 10 is sectional view showing furthe; details of the table control mechanism;

Figure 11 is an elevation of the oscillatory member forming one part of the reversing valve;

Figure 12 is a similar view of the reversing valve cap or closure; and

Figure 13 is a detail view showing the valve for Icy-passing the operating fluid to stop the machine during indexing.

The invention is illustrated in connection with a machine for grinding notched index plates such as are employed on gear cutting ma hines to insure extreme accuracy of spacing of the teeth of the gears being out. In the index plate grinding machine illustrated, the grinding wheel is mounted upon a reciprocating table and the index plate upon a rotatable work spindle which is loosed against rotation during the grinding operation. The reciprocating table is operr. filed January 12, Serial No. 332,125.

ated by fluid pressure and its movement is controlled by a reversing valvewhich is operated at the ends of the table stroke by adjustable stops secured to the table. During each cycle of movement of the table, the wor: spindle is indexed. For the purpose ot effecting the indexing, a third stop or lug is mounted on the table. This third stopis sopositioned that before the table has reached the limit of its working movement in one direction, it strikes and rotates a lever arm which is connected with a bypass valve and also with the dog that normally locks the work spindle against rotation. The movement of the lever arm releases the work spindle and simultaneously connects the indexing mechanism therewith; "the same time it opens the bypass valve toby-pass the motive fluid around the reversing valve and stop the table movement so that during indexing the table is station- As soon as theindexing is completed, the work spindle locks up again under actuation of a spring. The return movement or" the locking dog to locking position resets the lever arm andcloses the by-pass valve so that the table resumes its motion to grind a new tooth of the index plate. When the grinding of the index plate has been com pleted, the operator can withdraw the table to inoperative position to permit removal of the completed plate and chucking of a new plate by movement of a conveniently placed llandle which operates a lever which lifts the index trip lug and one of the limit stops out of operative position and permits the table to move beyond its predetermined limit working position. The table is brought to a stop automatically, when it has been withdrawn sufficiently for chucking, by a lug or stop on the table which operates a second by-pass valve.

Referring now to the drawings, 20 indicates the base or frame or the'machine. Mounted on this base or frame 20 is a reciprocable table or slide 21 which moves on the ways 22 and 23 (Fig. 1) formed on the base. The table 21 is providedon its upper face with a dove-tailed shaped guide way which extends transversely of the ways 22 and 23. Mounted in this guide way for adjustment on the table is a support or carrier 25 in which the grinding wheel spindle 26 is journaled at 27 and 28. The grinding wheel 30, which has, preferably, one flat and one conical grinding surface, is secured to the spindle 26 in any suitable manner. The frame or base 20 is provided on its front face with ways 32 and 33 which are inclined rearwardly from the bottom to the top of the base. Mounted for sliding adjustment on these ways is the work head or support 84 in which the work spindle 35 is journaled at 36 and 37. The work piece to be ground, which in the present instance is a notched index plate 40, is secured to the work spindle by any suitable means.

The tool support 25 can be adjusted toward and from the work spindle to position the grinding wheel 30 in operative relation with the work for grinding the notches ll therein by rotating the hand wheel 43 (Fig. 2). This hand wheel 13 is secured to a shaft (not shown) which carries a bevel gear (not shown) which meshes with the bevel gear a l (Fig. 1) which is secured to the screw shaft 15. This shaft is secured to the support 25 and threads into the nut 16 which is mounted against axial move ment in a bracket 47 which is fastened to the table 21. As will be obvious, by rotating the hand whel a3 in one or the other direction, the grinding wheel 30 can be adjusted toward or from the work. When the tool support 25 has been thus adjusted, it may be secured in its adjusted position by means of a T-bolt or bolts not shown which may be moved to clamping position by cranks or handles such as shown at 49.

The work support, as already indicated, is vertically adjustable upon the base or frame 20. This is for the purpose of bringing work pieces of different diameters into operative relation with the grinding wheel. This adjustment may be effected by rotating the hand wheel 50. This hand wheel is secured to a shaft 51 that carries a worm 52 which meshes with a worm wheel 53. The worm wheel is secured to a screw shaft 54: that threads into a nut 55 which is secured to a bracket 56 that is fastened to the base or frame 20 as by means of the bolts 57. The work support may be secured in any adjusted position by means of a T-bolt 58 that engages in a T-slot 59 which is formed in the base or frame 20 of the machine parallel to the ways 32 and 33. The T-bolt is moved to and from clamping position'by the crank or handle 60.

During the operation of the machine the grinding wheel 30 is rotated continuously being driven from the motor 62, which is mounted upon a bracket 63 that is secured to the base or frame of the machine, through the pulley 6t and 65 and the belting 66.

The side faces of the notches 41 of the index plate are ground by reciprocating the grinding wheel 30 across the face of the index plate. This reciprocating movement of the grinding wheel is effected by reciprocation of the slide 21 and the reciprocating movement of this table or slide 21 is effected by fluid pressure, fluid under pressure being admitted alternately to opposite ends of the cylinder which houses the piston 71 that is connected by the piston rod 72 with the table or slide 21. The cylinder is suitably mounted upon a shelf 74 formed integral with the base or frame 20 and the piston rod 7 2 is secured by a nut 7 5 to a depending lug 76 which is formed integral with the table or slide 21.

The reversal of the table 21 may be controlled by a reversing valve of any usual or suitable construction. The valve shown comprises an oscillatory ported member 80 (Fig. 11) which oscillates between stationary ported seat members 81 and 82 (Figs. 9 and 12). The control mechanism is indicated as a whole at 83 (Figs. 2 and 7).

The motive fluid is pumped from a sump 85 formed in the base of the machine through a pipe 86 by the pump 87 which may be of any usual or suitable construction. This pump 87 is driven from the motor 62 by the pulleys 88 and 89 and the belting 90. The pump 87 forces the fluid through the pipe 92, when the bypass valve 94 is closed, into the pipe 95.

The seat member 81 of the reversing valve has one recess or port 100 (Fig. 9) which is in constant communication with the supply pipe 95 and another independent recess or port 101 which is in constant communication with the return pipe 102 which returns the fluid to the sump 85.

The oscillatory ported member 80 has three apertures or ports therethrough, 105, 106 and 107. The seat members 82 has two apertures or ports 109 and 110 formed therein, one of which 109 communicates through the passage 112 (Fig. 10) with the pipe 113 leading to one end of the cylinder 70 (Fig. 2). The other port 110 in the seat member 82 communicates through the passage 115 with the pipe 116 which leads to the other end of the cylinder 70.

When the valve member 80 is rocked in one direction, the port 106 connects the port 100 in the seat member 81 with the port 109 in the other seat member 82, thus establishing communication between the supply pipe 95 and the pipe 113 leading to one end of the cylinder 70 to move the piston 71 to the left in said cylinder viewed from the bottom of the sheet containing Fig. 2. At the same time, the port 107 establishes communication between the exhaust port 101 in the seat member 81 and the port 110 in the seat member 82, thus exhausting the fluid from .seoa'zee the lefthand end .of-thepiston '71 through the pipe 116 and the pipe 102, \vlienceitis returned: to. the sump.

.lVhen the ported-member .80 :is rockedin the. opposite direction ifroin that already described, the port 10.6 .connectsfthe port 100 with the port 110 with the .result that athe pressure .fluid hows to the left hand .end of the cylinder I through thepipe 11.6. .It is simultaneously exhausted ifroin the right hand end. of this cylinder through the pipe 113, through the passage 1X33 1112, the port 109,;the port 105.ofzthe oscillatorymeinbe-r 80, the port 101 andthereturnpipe 102.

In the intermediate .or neutral .position of the valve member the port 5106.0verlaps the supply port .and also 513116 ports i109 and 110, while the ports and -:107are so disposed as :to establish communication between the ports 109 and 110, "respectively, and the exhaust port .101. As a; consequence, circulation of the pressure fiuidiis-perinitted Without building up .an excessive pressure. Since, through this arrangement, also, the fluid can escape .freely fromzthe cylinder 70 to the return pipe .102, the :table 271 can be shifted by;hand,as desired.

-Oscillationiof :the :valve member 80 isaccoinplished by oscillation of va shaft (Fig. .7) to which the:oseillatorymember 80 is secured. This shaft 120 carries aihandle or lever 121 (Figs. 2, 7 and 8) which works between a pair of stops 122. The lever 121 carries .a pin 124: which is received in a slot formed in the lower edge of a swinging plate 125. The swinging plate 12.5 is secured to-a rock shaft 126 (Figs. 2,3, 7 and 8). This rock shaft 126 carries at its rear end an arm 127 3), .the dipper end of which is disposed in the :path of a pair of spaced adjustable dogs or stops 129 and 1 0 carried by the table 21. These :stops 129 and 1301are-slidably adjustable in the groove or slot 131 formed in the lrear face of the slide or :table and can be secured in any adjusted position to limit the travel of the table 21 in any suitable manner.

lVhen the arm 127 is struck by one or other of the dogs 129 or 130, the shaft 126 is rocked inone or thelother direction to rock the plate 125. The plate is quickly snapped from one position to the other by the action of thezcoil spring (Figure which is secured at one end to the Valve casing and at the other end to a lever arm 13% that is provided with a V-shaped end cooperating with a diamond shaped block 136 that is secured to the rear of the plate 125.

The rocking (of the rock shaft 126 and the plate 125;alternately in opposite directions by the stops 112.9 and .130.. :as just described, serves to rock the valve member :80 first in one direction and then in the other to put 5 the pipes 1 an 1.16 altern tely o supply across the index :plate and when the table 21fhas moved far enoughthatzthe grinding wheel clears the plate, :the workspindle is indexed to bring a:newnotch of the index plate into position for grinding. The

means for .loclring'the work spindle against rotation during grinding and for indexing the work spindle will'now be described. Secured'to-the work spindle 35 atzits end opposite to the index plate 40 is a large wvorin wheel 15.0 (Figs. 1, 2 and 3). This worm J wheel is rotated "periodically for indexing through an are equal to the angular distance between notches of the zindex plate by a worm 1.51 (Figs. 2, 4,15and6) which is secured to a shaft- 152 that is journal'ed in bearings153 and l5 llin-abracketformed as an extension on the work support Mounted on this bracket is motor 155 (Figs. 1, .2 and 5:). :This .motor drives a worm 156 which meshes withand drives a worm wheel 15.7. The worn-1 wheel 157 %is keyed ztoa sleeve 159 which -is journaledion the shaft 160,1a suitable bushing .1161 being interposed between the-sleeve 159. and the shaft. ratchet teeth 162.

Keyed to the shaft 160 is :a sleeve which is enlarged at :its lower :end and lsu-rrounds the ratchet 162. Thisenlargediporti n 16.6 of :the sleeve 165 *is slotted around its periphery and between the upper and lower plates 16.7 and 1.68s0 formed',"-there is :pivotally mounted a1pawl169. This pawl 1 69 is normally :urged :into engagement with the ratchet teeth 162 by a springpressed plunger which is housed in the enlarged head portion 166. When the engages the teeth of the ratchet wheehthe rotation of the worm wheel 15? is transmitted to the shaft 160 which is then driven from the motor 155 through'the worm 156, the worm wheel 157, the ratchet wheel'162, the pawl 169 and the sleeve 165. :Secured :to the upper end ;of the shaft 160 is a spur gear 172 which forms one of a set- 0f index change gears 17-2, 173,174-and 175. The last named gear is secured to a sleeve 17:6 which is pro.- vided on its lower face with -.c1ut,ch teeth adapted to engage clutch teeth formed. on

the 211M191 face Qfa sleeve .177 which is 53.9?

The sleeve 159 'is provided with cured to the worm shaft 152. Through the mechanism described, it will be seen the worm wheel 150 may be rotated to index the notched plate 40.

The shaft 152 is provided with a polygonal shaped end to receive a crank or wrench for rotating the shaft 152 manually, when the clutch teeth of the sleeves 176 and 177 have been disengaged by unthreading of the nut 179, to enable manual adjustment of the notched plate 40 through a small angle to bring one or the other of the side faces of the teeth of the plate into operative relation with the grinding wheel 30.

The pawl 169 is held disengaged from the ratchet wheel 162 by one of a pair of stop dogs 180 and 181. The dog 181 is to be seen dotted below the dog 180 in Figure 5. The dogs 180 and 181 engage in notches (not shown) formed in the plates 167 and 168 to hold the sleeve 165 against rotation in either direction and when .so engaged, the dog 180 engages a tail-piece 183 formed on the pawl 169 to hold the pawl out of engagement with the ratchet teeth 162. Hence, when the do s 180 and 181 are engaged in the plates 167 and 168, the work spindle is held stationary.

These two dogs 180 and 181 are secured to a stud 185 which is journaled in a lug 186 securedsto the bracket which supports the index mechanism. Secured to this stud 185 at its lower end is a double armed lever 187.

The dogs 180 and 181 are rocked to and stop 196 which is adjustably secured to the table or slide 21 in any suitable manner. The shaft 190 is made telescopic and in three parts connected by universal joints in order to permit of the various machine adjustments required. 7

When the stop 196 strikes the arm 195 it rocks the shaft 190, rocking the lever arm 187 through the linkage 191, 192 moving the dogs 180 and 181 to disengaged position, releasing the sleeve 165 and permitting the pawl 169 to engage the ratchet wheel 162 to transmit the rotation of the ratchet wheel to the sleeve 165 and the shaft 160 to index the work spindle. formed at its outer end to provide a dog 197. This dog 197 is adapted to engage a notch 198 (Fig. 5) formed in a plate 199 whichis-secured to the lower end of a shaft 200. The arrangement is such that until the dog 197 is seated in this notch, the dogs The lever arm 187 is 180 and 181 cannot return to locking position.

The shaft 160 is provided at its lower end with teeth forming a spur pinion 201 (Fig. 4). This spur pinion meshes with and drives, when the shaft 160 is unlocked, a spur gear 202. The spur gear 202 is secured to the lower end of a shaft 203 which carries at its upper end a miter gear 20t. This miter gear 204: meshes with a second miter gear 205 that is fastened to a horizontal shaft 206 (Figs. 4: and 5). This shaft 206 carries a spur gear 207 which meshes with a spur gear 208 upon a shaft 209. This shaft 209 carries at its inner end a bevel gear 210 which meshes with and drives a bevel gear 211 upon the shaft 200 thereby rotating the stop plate 199.

The gears 207 and 208 constitute a pair of change gears which may be changed at will to vary-the ratio of rotation of the shaft 160 to the shaft 200. If the change gears 207 and 208 are selected, for instance, so that the shaft 160 will make two revolutions to one revolution of the shaft 200, then the shaft 160 must make two revolutions during indexing before the dog 197 can enter the notch 198 in the stop plate 199 and permit the dogs 180 and 181 to lock up the shaft 160 again and withdraw the pawl 169 from engagement with the ratchet wheel 162.

The dogs 180 and 181 are normally pressed into engagement with the stop plates 167 and 168 by a spring pressed plunger or plungers 215 (Fig. 5) housed in'the index bracket. It will be seen, then, that when the dogs 180 and 181 are rocked out of engagement with the plates 167 and 168, they will remain out of engagement until the shaft 200 has made the predetermined number of revolutions and that they will then be forced back into engagement with the plates 167 and 168, disengaging the pawl 169 and rocking the arm 195 (Fig. 3) back to its initial position, thus resetting this arm in position to be tripped again on the next movement of the table 21 to the left in Fig. 3.

To avoid too long an idle stroke of the table 21, it is desirable to stop the table while indexed. To this end, a bypass valve 94 (Figs. 2, 3 and 18) is interposed in the supply line between the pipes 92 and 95 and arrangement is made for operating this valve from the index trip arm 195 (Fig. 3). To this end, the shaft 190 carries intermediate its length a link 22 1 which is connected to a link 225'that is in turn connected to an arm 226 secured to a rock shaft 227 which carries an arm 228 (Figs. 3 and 13) which has a pin and slot connection with the piston 229 that slides in'the by-pass valve chamber 9 1, v

In the position shown in Figure 13, the

valve is closed permitting the motive fluid Y to flow freely from the pipe 92 into the pipe 95 and thence through the reversing valve to the cylinder 70. When, however, the valve or piston 229 is depressed by engagement'of the stop 196 with the arm 195, the ports 230 and in the lower end of the valve chamber are opened permitting the motive fluid to' bypass from the pipe 92 into these ports and drop back into the sump. Thus, when the valve 229 is depressed, the slide is stopped. When the locking dogs 180 and 181 are returned to locking position by the action of the sprin pressed plunger 215, the shaft 190 is rocke as already described and thus the by-pass valve is returned to the position shown in Figure 13 permitting the motive fluid once again to flow to the reverse valve and the cylinder 70.

The stop 196 is preferably adjusted so that it strikes the arm 195 to stop the ma chine and operate the index mechanism before the stop 180 strikes the arm 127 (Fig. 3) so that when the indexing has taken place and the machine is again started, it continues to move to the left to its limit position as determined by the stop 130 before reversing.

To take up back lash in the index mechanism during operation of the machine, the brake 235 (Figs. 2, e and 6) is mounted on the sleeve 177 and is adapted to place the worm' shaft 152 under a slight tension determined by the tension placed on the spring-238.

By rotating the shaft 240 (Figs. 2, 4L and 6) the index plate may be moved angularly to provide a fine feed adjustment relative to the grinding wheel. This shaft 240 carries aworm 2 11 which meshes with a worm wheel 2412 which is secured to a screw shaft 213 that is journaled in the index bracket parallel to the'worm shaft 152. This screw shaft 243 is threaded at its lower end into a nut 2&5 which is secured by the screws 2e6 to the member 24:? carrying the lower bearing 153 for the index worm shaft 152.

The dogs or stops 130 and 196 (Fig. 3) are pivotally mounted so that they can be lifted up out of the way of the arms 127 and 195, respectively, to permit movement of the grinding wheel 30 to inoperative position for removal of the index plate when ground and chucking of a new plate. These dogs 130 and 196 may be rocked to inoperative position manually by movement of the handle 250 (Fig. 2) which is secured to a rock shaft 251-which is journaled in the frame of the machine and carries at its rear end (Fig. 3) a link 252 which forms one member of a parallelogram linkage 252,

253, 25 1. The link 25 1 is pivotally mountet upon the base or frame for movement simultaneously with the link 252. When the parallelogram linkage is rocked upwardly by the operator, the link member 253 engages rollers 256 and 257 provided on the stops 130 and 195 respectively, to move the stops to inoperative position. When this is done, the table 21 moves onto the left withrock shaft 262 (Figs. 2 and 10). This shaft 262 i-ries at its inner end an arm 263 which engages theupper end of'the stem of a valve 265 which is normally pressed by the spring 266 into closed position. When the arm 261 is rocked by the step 260, the valve 265 is depressed against the resistance of thespring 266 putting the supply pipe 95 in communication with the exhaust pipe 102 throughthe passage 268 so that the pressure fluid that would otherwise flow to the cylinder is able to escape through the pas sages 142, 112 and 268 into the exhaust-pipe 102 returning thus to the sump and bringing the table to rest.

To return the table 21 to grindlng position, the operator simply reverses the reverse valve by rotating the handle1121 (Fig. 7). 111 the return movement of the table 21, the stops 130 and 196 simply rise up over'thelr respective arms 127 and 195 being pivotall'y mounted for this purpose. I

The grinding wheel may be dressed at any time to maintain a good operating surfaceon the wheel by a diamond28O (Fig. 2) which may be reciprocated or swung across the surface of the grinding wheel by rotation of the hand wheel 281.

and maybe clamped inany adjusted posi' tion by means of the hand lever 282.-

To maintain the belt 66 which drives the wheel spindle 26 taut, an idler 285 (Fig. 3) i may be provided; This is journaled inan arm 286 which is pivotally mountedat'287 from the base or frame. This arm 286has connected to it an arm 288 that carries a weight 289 which constantly urges theidler 285 to engagement with the belt 66.

While the present invention has been de scribed in connection'with a machine for grinding incex plates, it will be understood that it is not' limited to this purpose. In general, it may be said that this application is intended tocover any variations, uses,'or adaptations of this invention, following, in general, the principles of the'invention and including such departures from the present disclosureas come within known or'customary practice in the art to'whichthe invention pertains and as may be applied tothe essential features hereinbeforeset forth and as fall within'the limits of the invention or the scope of the appended claims.

The diamond support will be made adjustable as usual Having thus described my invention, what I claim is:

1. In a machine of the class described, a work spindle, indexing mechanism for imparting a step-bystep rotary movement to the work sp ndle, a reciprocable table, a tool aartina a ste -b -ste 3 rotarv movement to the work spindle, a reciprocable table, a tool mounted onthe table, adjustable stops on the table for controlling the movement thereof, a lug mounted on the table for stopping the movement of the table and actuating said index mechanism-before the table has reached the limit of its movement in one direction and means operable, when the indexing has taken place, to re-start said table.

3. In a machine of the class described, a work spindle, means for locking the work spindle against rotation during operation on the Work piece, indexing mechanism for imparting a step-by-step rotary movement to the work spindle, a reciprocable table, a tool mounted on the table, adjustable stops on the table for controlling the movement of the table, a lug mounted on the table and means connected with said locking means and operable by said lug for stopping the movement of the table and simultaneously releasing said locking'means and connecting the index mechanism with the work spindle and means for restarting the machine after indexing has taken place.

i. In a machine of the class described, a

work spindle, indexing mechanism for impartmg a step-by-step rotary movement to the work spindle, a table reciprocable by a fluid under pressure, a reversing valve for the pressure fluid, adjustable stops on the table for operating said valve, a valve for by-passing the pressure fluid around the reversing valve, a lug on the table for operating the by-pass valve, and means actuated simultaneously with the operation of said by-pass valve for actuating the index mechanism.

5. In a machine of the class described, a work spindle, index mechanism for imparting a step-by-step rotary movement to the work spindle, a table reciprocable by fluid under pressure, a reversing valve for the pressure fluid, adjustable stopson the table for operating said valve, a valve for bypassing the pressure fluid around the reversing valve, a lug on the table for opening the by-pass valve to stop the table, means acting simultaneously with the opening of said by-pass valve for actuating the index mechanism, and means for closing the bypass valve automatically when indexing has taken place to restart the table automatically.

6. In a machine of the class described, a

work spindle, indexing mechanism for imparting a step-by-step rotary movement to the work spindle, a table reciprocable by fluid under pressure, a reversing valve for the pressure fiuid, adjustable stops on the table for operating said valve to determine the working path of said table, a lug on the table for actuating the index mechanism, and means interposable in the path of said lug and one of said stops to render both inoperative and permit withdrawal of the table from working position, and means responsive to said withdrawal movement for to stop the table when the index mechanism is actuated and to allow the table to con tinue its movement when indexing has been completed and means for moving the lug and one stop to inoperative position to permit withdrawal of the table from its workingpath. V

8. In a machine of the class described, a work spindle, indexing mechanism for imparting a step-bystep rotary movement to the work spindle, means normally locking the work spindle against movement, a table reciprocable by fluid under pressure, a reversing valve forthe pressure fluid, adjustable stops on-the table for operating said valve, a valve for by-passing the. fluid to stop the table, a lug secured to the table, a member operated by said lug to release the locking means and permit indexing of the work spindle, means forreturning the locking means and said member to position after the. work spindle has been .indexed,'and means responsive to themovement of said member for opening and closing the bypass valve. r r V 9. In a machine of the class described, a work spindle, indexing mechanism for imparting a step-by-step rotary movement to the work spindle, a locking dog, means constantly urging said dog into locking relation with said work spindle to secure the same against movement, a table reciprocable by fluid under pressure, a reversing valve for the pressure fluid, adjustable stops on the table for operating said valve, a lug secured to the table, a valve for by-passing the fluid to stop the table, a lever operable by the lug to release the locking means and connect the indexing mechanism with the work spindle to index the same, means for returning the locking means and said memher to position after indexing has been completed, means responsive to the movement of said member for opening and closing the by-pass valve and means for moving said lug and one of said stops to inoperative position to permit withdrawal of said table to inoperative position.

10. In a machine of the class described, a work spindle, a reciprocable table, means operated by fluid pressure for reciprocating said table, indexing mechanism for imparting a step-by-step rotary movement to the work spindle, a valve for by-passing the pressure fluid to stop the table, and a common control device for the indexing mechanism and said valve.

11. In a machine of the class described, a work spindle, a reciprocable table, means operated by fluid pressure for reciprocating said table, stops for controlling the limits of the table movement, indexing mechanism for imparting a step-by-step rotary movement to the work spindle, a valve'for bypassing the pressure fluid to stop the table, a common control device for the indexing mechanism and said valve operable intermediate the limits of working movement of the table, and means for rendering one of said stops and the control device inoperative to permit withdrawal of the table from its working path.

12. In a machine of the class described, a work spindle, indexing mechanism for imparting a step-by-step rotary movement to the work spindle, a reciprocable table, means adapted to be tripped intermediate the limits of the movement of the table for actuating the indexing mechanism, and means for stopping the table simultaneously with the actuation of the indexing mechanism.

13. In a machine of the class described, a work spindle, indexing mechanism for imparting a step-by-step rotary movement to the work spindle, a reciprocable table, means adapted to be tripped intermediate the limits of the table movement for actuating the indexing mechanism, means for stopping the table simultaneously with the actuation of the indexing mechanism, and means for restarting the table when the work spindle has been indexed.

1 1-. In a machine of the class described, a work spindle, continuously operative drive means adapted, when connected to the work spindle, to impart an indexing movement to the spindle, locking means adapted to prevent connection of said drive to the work spindle during the working operation, a table reciprocable by fluid under pressure, a reversing valve for the pressure fluid, a valve for by-passing the pressure fluid around the reversing valve, and a common control device controlling the locking means and said by-pass valve adapted to be operated intermediate the limits of movement of the table to stop the table and simultan ously release said locking means and permit connection of the drive to the work spindle, and means for disconnecting the drive, returning said locking means to operative position, and restarting the table when the work spindle has been indexed.

RAYMOND WEBSTER. 

